Doug’s MATLAB Video Tutorials

April 17th, 2008

11:39 UTC | Posted in Format: PodCast, Format: Video, Level: Advanced, Topic: GUI or GUIDE | Permalink |

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16 Responses to “Advanced MATLAB: Handles and other inputs to GUIDE callbacks”

1. Quan replied on April 17th, 2008 at 17:15 UTC :
   

   Nice video as usual. You need a nickname of some sorts . . . I was thinking “The MATLAB Evangelist” might a good one.

   But seriously, good videos. I want to start linking them from blinkdagger because I think the tutorials supplement each other very well.

2. naor replied on April 17th, 2008 at 19:49 UTC :
   

   Doug,
   Can you explain about guidata(hObject,handles)? I thought this was necessary after any change to handles.
   Thanks

3. Doug replied on April 18th, 2008 at 08:15 UTC :
   

   Quan,

   We actually had “MATLAB Evangelist” as a title for while when Scott was looking for people. Looks like we took that out of the title, but there are plenty of jobs like that for MATLAB geeks.

   http://www.mathworks.com/company/jobs/opportunities/ApplicationEngineering.html

   Send me a resume, we will see what we can do.

   Doug

4. Doug replied on April 18th, 2008 at 08:17 UTC :
   

   Naor,

   About GUIDATA: That is a a different way of interacting with handles. I prefer handles to be more of a read-only type of structure. If I want to store data, then I advocate SETAPPDATA. See my video on this:

   http://www.mathworks.com/matlabcentral/fileexchange/loadFile.do?objectId=8616&objectType=FILE

   Doug

5. jiro replied on April 18th, 2008 at 15:21 UTC :
   

   Quan,

   There’s actually 6 of us at The MathWorks with an internal title of “LTC Evangelist” (LTC = Language of Technical Computing = MATLAB). I am one of them, and Doug used to be in this group as well.

6. amiryousuf replied on May 6th, 2008 at 03:31 UTC :
   

   Hello, Can we output data entered by user in dialogbox to command window?
   thanks in advance.

7. Administrator replied on May 6th, 2008 at 11:00 UTC :
   

   Amir,

   You would simply modify the callback to use the DISP command to display any data you want.

   Doug

8. amiryousuf replied on May 7th, 2008 at 06:53 UTC :
   

   thanks for the idea. it is working.

9. Tayfun replied on July 27th, 2008 at 06:38 UTC :
   

   ıt is very good video. I learn a lot of new things about gui

10. Zach replied on October 27th, 2008 at 16:57 UTC :
    

    Doug,
    I have a GUI that I put a timer in so that it will check if any serial data has come in every second. I am having trouble getting the Timer to pass the handles structure to my function that is plopped into the M-file that guide made. On compile it says that the “handles” is undefined. I tried to pass the hadles from the Timer funtion by saying {@myfunction, handles} to pass the handles to the myfunction but I get another compile problem. any help would be great.

11. Doug replied on October 29th, 2008 at 14:34 UTC :
    

    Zach,

    I think that the GETAPPDATA, SETAPPDATA techniques shown here:

    http://blogs.mathworks.com/pick/2005/10/03/guide-video-part-two/

    Might be an easy solution for you.

    Doug

12. Zach replied on October 29th, 2008 at 22:37 UTC :
    

    Doug,
    I cant get the file to play from link or by going to list??

13. Doug replied on October 31st, 2008 at 08:59 UTC :
    

    I have tested, it is working now.

    Doug

14. Zach replied on November 5th, 2008 at 18:14 UTC :
    

    Doug,
    It seems like the handles structure is already there and ready to use. The timer that I made in the OpeningFcn needs to pass the args similar to the widgets on the GUI send, in particular the “handles” part of MyFunct(hObject, eventdata, handles). In the timer object you can specify the args to pass but I think Im having a problem getting the handles to pass through properly. This is what I am trying handles.t = timer(’TimerFcn’,{@GetSmp_Callback, handles} , ‘Period’, 1,’ExecutionMode’,…
    ‘fixedspacing’,’startdelay’,1); I initialize this in openingFcn but I am not sure if im handing “handles” properly. Is there a way to use a timer in the GUI and also use the handles structure? I can use set/getappdata but then all the wigets and callbacks use handles structure.

15. dhull replied on November 11th, 2008 at 16:35 UTC :
    

    The timer will be running in its own little workspace, so the handles structure that you pass at the beginning of the timer will be whatever it was when you create the timer.

    Try this in the opening function:

    t = timer(’TimerFcn’,{@foofoo, handles} , ‘Period’, 1,’ExecutionMode’, …
    ‘fixedspacing’,’startdelay’,1);

    start(t)

    With this function on the path.

    function foofoo(obj, event, hand)
    disp(hand)

    A silly little function, but it gets the handles structure out there as you see.

    -Doug

16. wrn replied on December 17th, 2008 at 21:34 UTC :
    

    Doug,
    I want to do the thing like Zach.

    I have a GUI that contain many axes.

    But when I call the function with timer or serial callback.

    when I use like in this example
    http://blogs.mathworks.com/pick/2005/10/03/guide-video-part-two/

    like this
    part from my updateAxes function.

    hAxes = findobj(hMainGui, ‘type’, ‘axes’); axes(hAxes(1));
    plot ….

    The axes will not be in my main GUI but another new window.

    I guess that the reason for this is because, my function is not calling in GUIDE callback scope(it’s called from timer or serial callback). Like it work only if I invoke updateAxes from another callback function from GUI.

    How can I do it, the update have to invoke when the new data is come.

    Thank you very much.

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a = magic(3);
sum(a)
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